I agree with the brake comment, certainly check the rotors. Really there are few things that can make the front end wobble (and fewer things in the rear).
*Steering - worn tie rod ends or center link.
*Bushings - either upper or lower control arm bushings, however most of the time the uppers tend to go first
*Ball Joints - sometimes they have grease fittings, but they are easy enough to check with a small pry-bar
*Bearings - They can either wear out or need repacking. See
http://www.planetisuzoo.com/articles.htm/56 for a howto on bearing repacking.
*Brakes - if a rotor is extremely warped, it can cause the wheel to wobble when driving. This can usually also be felt in the brake pedal when braking.
*Tires - not just balance, but out of round tires can cause problems. (I have 4 tires, and they can't be rotated. If I swap any of them to another position on the vehicle, the truck pulls or wobbles)
Just work through the list to eliminate those items.
-Tad